Wellhead



Dec. 2l, 1943. H. ALLEN 2,337,221

WELL HEAD Filed Nov. 7, 1938 '7 Sheets-Sheet 1 HERBERT ALLEN im wwwATTORNEYS.

H. ALLEN Filed Nov. 7, 1938 'T Sheets-Sheet 2 gag@ HERBERT ALLENATTORNEYS.

Dec. 21, 1943. H. ALLEN 2,337,221

WELL HEAD Filed Nov. 7, 1958 7 sheets-sheet 5 HERBERT ALLEN BY @and ATTORNFYS,

Dec. 21, 1943. H. ALLEN 2,337,221

WELL HEAD Filed Nov. 7, 1938 '7 Sheets-Sheet 4 HERERT ALLEN ATTORNEYS.

Dec. 21, 1943. H. ALLEN 2,337,221

WELL HEAD I Filed Nov. 7, 1938 7 SheetsSheet 5 ATTORNEYS.

Dec, 21, 1943. H. ALLEN 2,337,221

WELL HEAD Filed Nov. '7, 1938 7 Sheets-Sheet 6 HERBERT A I LE NATTORNEYS.

H. ALLEN Dec. 21, 1943.

WELL HEAD 7 Sheets-Sheet 7 Filed Nov. '7, 1938 HERBERT ALLEN @im nIIIIIIIIIIIIIII vfvwis t AWORNEYS.

Patented Dec. 21, 1943 WELLHEAD Herbert Allen, Houston, Te'x.,assignorto Cameron Iron Works, Houston. Tex.

Application November 7, 1938, Serial No. 239,320

11 Claims'. (Cl. 285-22) The invention relates to a well headconstruction whereby a seal is maintained at the head to prevent leakagebetween the tubing and the casing and at the same time to hold thetubing ilrmly in position.

Various types of casing and tubing seals have been provided heretoforebut in practically all of them there has been no provision for anytolerance in the manufacture of the parts and it is almost impossible toso construct the tubing hangers and the casing head so that they will tprecisely one with the other. It is therefore necessary that a seal beprovided to close the area between the hanger and the casing-head, whichseal will have some exi'bility in its adaptation of the parts so that apositive seal will be maintained even though the parts are of slightlydifferent size or fit.

It is one of the objects of the invention to provide a casing seal ringand a tubing seal ring in combination with an adapter ring againstwhichthe seal rings will abut to equalize the applied pressure and fitthemselves into position.

Another object of the invention is to provide a combination seal andhold-down for tubing hangers wherein any inequality of the parts iscompensated for by adjustment of the sealing assembly, so as to form apositive seal.

A still further object of the invention is to provide a latchingassembly for tubing hangers which may be sealed in position.

'Still another object of the invention is to provide various types ofsealing and adapter rings for well heads.

Other and further objects of the invention will be readily apparent whenthe following description is considered in connection with theaccompanying drawings, wherein:

Fig. 1 is a side elevation of a well head in which the tubing hanger isbeing inserted, illustrating the arrangement of the blowout preventer onthe casing head through which the tubing hanger is lowered.

Fig. 2 is a view similar to Fig. 1 but showing the hanger landed inposition, the larger blowout preventer removed and a spool and smallervalve applied to the top thereof with the tubing hanger sealed inposition.

Fig. 3 is a magnied view ofthe seal and holddown for the hanger.

Fig. 4 shows a form of the hold-down and seal wherein the hanger islatched against removal.

Fig. 5 .is a section taken on the line 5-5 of Fig. 4.

Fig. 6 shows a modified form of the seal and hold-down wherein anadapter ring is arranged to bear against two spaced sealing rings,

Fig. 7 shows a seal wherein the adapter and seal rings have beencombined intoone element which is of irregular cross section.

Fig. 8 shows another form of the single ring which is substantiallyT-shaped in cross section.

Fig. 9 shows a. form of the hold-down and seal where a number of ringsabut together in order to permit equalization of the parts.

Fig. 10 is another form of the seal wherein a tongue portion in thehold-down member compensates for inequalities of the parts.

Fig. 11 is a View of the casing and hold-down seal which may be usedwhen no tubing hanger is present.

Fig. 12 illustrates a construction for the casing of Fig. 11 where atubing .hanger is to be sealed and held in position.

Fig. 13 shows a sectional view of a hanger which is welded to the pipeon location at the time the exact elevation of the top of the tubing hasbeen ascertained.

Fig, 14 shows an assembly where the tubing is supported on slips in thecasinghead and then a'ilange applied thereto by which a, seal andhold-down is provided.

Fig. 15 is a view similar to Fig. 14 but illustrating a Wiper at thebottom of the assembly so that a seal will be maintained with the tubingas it is landed into the hole and before it is landed in position.

Fig. 16 shows a form of hold-down flange which may be attached to thetubing when it has been cut off at the elevation where it is to besuspended and can be used with the construction of Figs. 14 and 15 wherethe tubing is supported on slips.

In Fig. 1 the well casing is indicated generally at 2 and issurmountedvby a casinghead 3. This head has the usual flow openings Iand 5 thereon and the flange 6 extends laterally at the top. The insidebore 1 is enlarged near the top to provide a seat 8 for the tubinghanger which is of a shape to be deposited into the enlarged area 9,directly above the seat.

'I'he upper surface I0 of the head may be slightly raised at il and justoutside of the cylindrical area 9 it is provided with an annular grooveI2 which will be designated as the casinghead groove. A casing seal ringI3 is disposed in this groove'and cooperates with any type of fittingwhich has a groove therein which may be deposited on the well head.

In the drilling operation, as illustrated in Fig.

l, a drilling valve. blowout preventer and gate valve. as circumstancesmay require, will be attached by the bolts I5 to the casinghead.

In Fig. l a blowout preventer I6 is so attached and is merelyillustrative of any desired type of fitting. Attention is directed tothe fact that the size of the bore I'I in this fitting I6 is such thatit will permit the lowering of the tubing hanger I8 therethrough, sothat the string of tubing 20 may be lowered into position and landedwith the shoulder 2! of the tubing hanger on the seat 8 in thecasinghead while the drilling equipment I8 is still in position. Thelowering of this string of tubing is accomplished by means of a settingpipe or nipple 23 which is engaged in the threads 24 on the inside ofthe top of the tubing hanger I8.

Fig. 2 shows an assembly after the tubing hanger I8 has been landed inposition in its seat. 'I'he drilling fitting I6 has been removed becauseit is of larger size and is an expensive piece of equipment. It is notdesired that this expensive equipment remain on the well as a permanentfitting because it may be used on other wells and the assembly of Fig. 2illustrates a construction by which the large fitting I6 may be replacedby a. smaller fitting 21. In order to reduce the size of the parts so asto support the smaller fitting 21 an adapter spool 29 has been attachedto the casinghead 3.

The spool 29 has a lower flange 38 and an inside bore 3| which is of asize to fit about the upper portion 32 of the hanger I8. Flowconnections 33 may be provided on the spool 28 and the upper flange 34is arranged to receive the fiange 35 of the fitting 21. In this mannerthe size of the bore is reduced to substantially that of the tubing 20and the fitting 21 is much less expensive and is not constructed towithstand as high pressures as is the fitting I6.

The tubing hanger I8 must be held down in position and must be sealed inthis position.

It has been found in practice that rubber and composition packingsdeteriorate quickly. due to the presence of the oil and gas and that itis therefore desired to secure a metal hold-down and seal constructionfor well heads of this sort. Such an assembly is illustrated at 40 inFig. 2 and a magnified view thereof is seen in Fig. 3. 'I'he edge of thetubing hanger I8 is shown at the left of Fig. 3 while the upper face I0of the casinghead 3 is illustrated in the lower right hand corner ofFig. 3. The casing groove l2 carries the casing seal ring I3 which hasbeen referred to previously.

The joint 4I between the hanger I8 and the bore 9 of the casinghead 3must be sealed to prevent the escape of pressure upwardly outside of thetubing and inside of the casing.

It is expensive and difcult to measure the bore 9 and the seat 8 on theone hand and the periphery of the tubing hanger I8 and the shoulder 2Ithereon on the other hand so that any two of them Winch may be assembledtogether in the field will be an exact t. In other instances the seat 8may be disflgured or damaged during the. drilling operations by thedrilling tools being lowered and raised in the well bore so that whenthe.5 drilling has been completed and it is desired to'.'

seat the hanger I 8 therein, it is impossible to' obtain a seal at theseat 8.

Thus in the majority of instances when the tubing hanger is deposited onthe seat 8 there will be inequalities in the parts so that it isimpossible to insure that the shoulder 42 on the hanger will be at theexact elevation of the top of the face II on the top of the hanger. Someprior practices provide for a seal ring at the junction of the hangerand the casing but due to inequalities it is practically impossible toseat a ring at this point and maintain a seal. There must be a certainamount of flexibility in the joint to allow for differences in size andpositioning in the parts.

The present invention contemplates a series of sealing assemblies whichwill admit of such exibility.

In Fig. 3 the hanger I8 has been provided With an outstandingenlargement 44 which has an outwardly 'and downwardly inclined shoulderor seat 45. -In order to allow for adjustment of the parts a cutoutsection 46 is provided directly above the shoulder and a lip 41 projectsabove the shoulder 45.

An adapter ring 5U is shown as having been deposited on the casinghead3. This adapter ring has a sealing shoulder 5I on the lower outsidecorner which is arranged to abut the upper edge of the casing seal ringI3. It has an inwardly projecting lower portion 52 which will abutagainst the periphery of the enlargement 44 and the outer periphery ofthe ring is arranged to abut the inside face 55 of a downwardlyprojecting iiange 56 on the spool 29 or such other fittings as may bedeposited on the casinghead 3.

The upper inside portion of the ring 58 is also formed with a shoulderor inclined face 51 which is arranged to abut the inside lower edge ofthe tubing seal ring 58 which seal ring is wedged against the seat 45 onthe tubing hanger by being held downwardly in the groove 59 which isformed on the bottom of the spool 29 or other fitting which groove isinside of the flange 56. The inside of the groove 59 is defined by a lip60 which may have some flexibility to allow a slight amount of movementof the ring 58 so that the lip 60 may be forced against the lip 41 onthe hanger I8. The spool 29 or other fitting will be drawn firmlyagainst this sealing assembly by the bolts I5.

It seems obvious from the foregoing construction that there is a greatdeal of exibility in the parts of this sealing assembly because if thehanger I8 does not move to its exact position, as seen in Fig. 3, thecut away portion beneath the enlargement 44 will allow for such aposition of the hanger and the adapter ring 50 will then fit against theenlargement in a slightly lower position. 'Ihis will mean that thetubing seal ring 58 will merely seat in a position a little further downon the seat 45 and a little further up on the seat 51 and that thecasing ring I3 will be wedged outwardly a little more.

On the other hand if the tubing hanger I8 moves downwardly further thanthe position shown in Fig. 3, just the opposite of the position of theparts just described will occur.

'Ihe fact remains that there are three elements, a casing seal ring I3,an adapter ring 50 and the tubing seal ring 58, all of which may yieldto some extent and which will fit faces together to provide a seal.Thus, irrespective of any differences of size or construction of theparts, a positive seal is insured.

Fig. 4 shows an assembly which will be utilized upon a seal whereenormous pressures are contemplated and where it is desired to insurethat the tubing will not be blown from its seat when the drillingfittings I6 are removed and before rThis latching assembly 61 may bethreaded or otherwise fixed to the portion 86 and `in Fig. 4 a lockingset screw 68 has been provided. The assembly 61 carries a plurality ,ofdogs 10 which are radially moved and normally held outwardly by tion inFig. 5.

member su. rtdwm be noted that this groove 88 is of such a width that itspans both of lthe rings I3 and 58. Any inequalities inthe parts arecompensated for by adjustment of the three rings I3, 58`and 84 so that.they ilt together and provide a seal because the rings may engage theinclined face 88 of the adapter ring 'at different y points along theface, depending upon the posimeans of springs 1I. These dogs are seen insecl A casinghead 3 has been provided with downwardly facing shoulders13 which are disposed at intervals circumferentially around on theinside. Between these shoulders are open spaces so that the hanger 65may be moved upwardly even though the dogs 10 are extended. When thehanger is inserted the dogsmay or may vnot pass through these openingsbut if they pass over a shoulder 13, they will be forced inwardly andthen snapped outwardly again against the shoullder. The hanger 85' willbe set by means of a setting pipe or nipple 23 which will be engaged inthe threads 24, preferably with a right hand thread.

In this manner the tubing hanger is lowered into position, the dogs 10snapped under the shoulder 13-and then the setting pipe is rotated tothe left to unscrew it. This rotation will turn the hanger 65 in acounter clockwise direction, as viewed in Fig. 5 until the dog 10 abutsagainst the stop rib 15. At this time the operator knows that the dogsare underneath the shoulder 13 and continued rotation permits theunscrewing of the setting nipple to leave the hanger latched in thecasinghead.

When the hanger is to be removed, the setting nipple 23 is reinsertedand turned to the right until the threads 24 are made up. The hanger 65then turns to the right in a clockwise direction until the dogs 10engage the stop rib 15, as seen in Fig. 5. When the operator cannot turnhis setting pipe any more. he knows that the dogs have been turned sothat they have moved outwardly from beneath the shoulder 13 and thetubing hanger can now be removed.

Fig. 4 shows a packing 80 which is carried beneath a shoulder 8| on thehanger.' This packing may be compressed by the weight of the tubing.

A sealing assembly 40 which has been previously described can be aiiixedover the tubing hanger 65 so as to hold it in position.

Fig. 6 shows another form of construction wherein the sealing assembly40 has been modied somewhat in that the tubing seal ring 58 has beendeposited in a groove 83'in the upper face of the hanger |8 but isconfined by the lip 60 on the hold-down fitting 85 which is equivalentto the spool or other tting 29, but which may Casing gIOOVB.

tion of the hanger and the hold-down member.

Fig. '1 shows another form of construction wherein the hold-down member85 is the same as described in connection with Fig. 6. The

hanger I8 is substantially the same as shown in Fig. 2, in that it isprovided with the shoulder 45, the lip 41 and the bottomshoulder 2|. In

this form ofthe invention the casing ring I3, the adapter ring 50 andthe tubing ring 58 have all been combined into a single seal ring 9|.This ring has a downwardly directed portion 92 which engages in thecasing groove I2 and has an enlarged irregular` body portion 93 whichwillflt into the spanning groove 89 and will also have a curved portionv94 which will engage the seal shoulder 45 on the hanger I8 and will alsoengage the lip 41 on the hold-down member 85. This ring will havesuflicient flexibility to accommodate adjustment of the parts.

Fig. 8 shows a form almost identical with that of Fig. '1 except'thatthe spanning groove 89 has been made of an irregular configuration topro- 'vide an arcuate groove 91 which tapers off to the lip 41. The sealring 98 is substantially T-shaped in cross section with the wider headfacing outlobe 99 on the `lower side fits in the casing groove I2 andthe upper lobe |00 ilts in the groove 91. 1

It seems obvious that this ring can tilt slightly to accommodate itselfto vthe parts.

Fig. 9 shows another form wherein the tubing hanger I8 is the same asshown in Fig. 6 in that the casing groove I2 and the tubing groove 83are at substantially-the same elevation. The holddown member 85 is thesame as seen in Fig. 6. In Fig. 9, however, the sealing assembly 40 ismade up of an inner sealv ring |02 and an outer seal ring |03. These tworings each have a downwardly facing ange or lobe |05 which, onthe Vinnerring is arranged to engage-in the tubing groove and in the outer ring toengage in the The upper curved face |06 on each ring is arrangedtoengage the edges of the be the permanent fitting 21 which ispositioned which will engage with the rings I3 and 58 and its uppersurface is curved at 81 so that it will engage against the base 88 of awide groove 89 `whichlis `formed the body ofl the hold-down spanninggroove 89 which will tend to wedge the two rings together. Each ring isprovided with a smooth contact face |01 and these two faces on the tworings abut together. In this manner any difference in elevation betweenthe casing and the hanger will be compensated for'by the positioning ofthese faces at `slightly different elevations. The tighter the hold-downmember 85 is drawn down, the tighter the parts will 'be wedged together.

Fig. 10 shows an arrangement similar to Fig. 9. except that thehold-down member 85 has been modified to provide an inner slot I I0 andan outer slot III. These slots are upwardly inclined toward each otherand create a tongue or flange ||2 which is supported by the narrow neckportion I I3 so that it will have some flexibility when it is forcedagainst the casing ring I3 and the tubing ring 58. AIn thismanner'anyinequalities of the parts will be compensated for. 'Fig. 11shows a form wherein the casing head 3 has its upper face I0 modifiedsomewhat in that it has an upstanding annular rib I|5 which' has adownwardly and inwardly inclined face H6.

The casing groove I2 is provided at the base o! this face. The hold-downmember 85 has a narrow groove |1 therein which is arranged to receivethe seal ring ||8. 'I'his form of construction may be used where notubing hanger is to be held down or slid in place, and may be usedduring the drilling operation to provide a seal.

Fig. 12 shows the same type of casing head as illustrated in Fig. 11where the tubing hanger I8 is to be slid in position and the hold-downmember 85 has a wide spanning groove 89 which has been previouslydescribed. A seal ring |20 having a substantially square cross sectionis disposed between the parts and has four rounded shoulders |2| thereonwhich will engage with the edges of the spanning groove 88, with theface H6 and with the shoulder 45 on the hanger Hl, This ring may iltitself in between these four contacts to provide a seal.

In many instances it is impossible to determine prior to the setting theexact elevation at which the tubing is to be suspended and in manyinstances after this elevation has been determined the tubing 20 must becut of! and then threaded to receive the hanger |8 so that it may besuspended at the desired elevation. This operation is often inconvenientand Fig. 13 shows an arrangement whereby the hanger I8 may be slippedover the tubing 28 after it has been cut oiT and the tubing flangedoutwardly at |25 so that a bead of welding material |26 may be depositedaround the top of the hanger to anchor it ilrmly on the pipe. The hangerhas all of the parts described in Figs. 2 and 3 and may be sealed inposition in the casinghead.

Fig. 14 shows an arrangement whereby the tub-ing will be suspended inthe casing head 8 by means of a tapered bowl |30 which is arranged toreceive a set of slips |3| These slips support the tubing 20.

In order to provide a hold-down for such an arrangement a hold-downilange |33 has been welded to the tubing by the bead |34 of weldingmaterial so that it is iirmly fixed to the tubing. This hold-down |33 isformed on its lower outside face |35 with the shoulder and enlargementswhich have been previously described in connection with the tubing |8 inFig. 3. In this manner the sealing assembly 40 can be applied and heldin position by hold-down member 85.

Fig. shows the same construction as illustrated in Fig. 14 except that ailexible wiper member |40 has been applied to the bottom of the adapterbowl |30 by being attached to the cut away shoulder |4| This wiper is ofa' exible material such that it will yield suiliciently to permit thepassing of the packings on the tubing as they are lowered into the wellbore but in event there is an upward pressure, it will tend to form aseal by clinging to the tubing and after the slips |3| have been placedit will tend to prevent any leakage until such time as the seal assembly4|.2 and the hold-down member 85 are positioned.

Fig. 16 shows another form of the hold-down ilange |33 which may beapplied to the tubing without either threading or welding and includes abody portion |50 which has a recess at |5| to receive the packing rings|52, which rings are held in position by a gland |53 which is threadedto the inside of the body |50. This ilange |38 is provided externallywith the shoulder 45 the same as the hanger I8. This construction can beapplied to thel tubing as soon as it is cut of! and the overhanging lip|54 on the gland |58 will prevent the tubing 28 from moving upwardlywhen the ilange is anchored by the sealing assembly and the packing |52will prevent leakage along the periphery oi' the tubing.

Broadly the invention contemplates a sealing assembly for well heads andtubing hangers which will have a considerable amount of flexibility toaccommodate inequality of the parts and to still maintain a seal.

What is claimed is:

1. A well head including a casing head, circumferentially spaced lugstherein having downwardly facing shoulders, a tubing hanger, springloaded dogs thereon to snap under said shoulders to latch said hanger, astop member adjacent one of said lugs to be engaged by a dog when thehanger is latched so that a setting pipe may be unscrewed from saidhanger and to be engaged by another o1' said dogs when said hanger isrotated in the opposite direction to reconnect the setting pipe to thehanger to indicate that the dogs have moved to a position from beneathsaid hanger so as to be removed.

2. A well head, a slip adapter bowl therein, slips in said bowl, a pipesupported in said slips, a hold down ange welded to said pipe above saidslips, a shoulder on said ilange, a seal ring on said head, an adapterring thereon having a shoulder, a tubing seal ring abutting saidshoulders, and a hold down member to force said tubing ring to sealingposition and to engage said ilrst seal ring.

3. A well head, a slip adapter bowl therein, slips in said bowl, a pipesupported in said slips, a hold down flange welded to said pipe abovesaid slips, a shoulder on said ange, a seal ring on said head, anadapter ring thereon having a shoulder, a tubing seal ring abutting saidshoulders, a hold down member to force said tubing ring to sealingposition and to engage said first seal ring, and a wiper member carriedby said adapter bowl to seal about said pipe before said seal rings arepositioned.

4. A packing connection to provide a seal between adjacent ilangesincluding a groove in each ilange, a metal seal ring in each groove, afiller member between said rings, sealing faces on said illler to forcethe upper metal seal ring inwardly and the lower metal seal ringoutwardly.

5. A packing connection to provide a seal between adjacent angesincluding a groove in each ilange, a metal seal ring in each groove, anda filler member between said rings, said grooves being oil'setvertically so that said'rlngs wedge against diagonal faces of said llermember.

6. A well head assembly including a casing head, a string of pipetherein, a slip adapter and set of slips in said casing head supportingthe string of pipe, a holddown flange above said slips about said pipeand weld amxing the flange to the pipe above the slips, and means toclamp said ange to the casing head.

7. A well head assembly including a casing head, a string of pipetherein, a slip adapter Aand set oi' slips in said casing headsupporting the string of pipe, a holddown ilange above said slips aboutsaid pipe, a weld aixing the flange to the pipe above the slips, meansto clamp said ilange to the casing head, and means to seal between thepipe and casing head below the slips.

8. A well head assembly including a casing head, a set of slipssupported therein to receive a string oi' pipe in the well, means toseal about the pipe and against the inside of the casing head below theslips, a holddown flange welded to the pipe, and means to clamp theilange to the casing head.

9. A metal sealing assembly to provide a seal between two members and anadjacent third member including a seal ring to contact one of themembers and the third member, metal gasket to contact the other memberand the third member, and a filler ring to seal with the seal ring andthe gasket.

10. A metal sealing assembly to provide a seal between two members andan adjacent third member including a seal ring to contact one of themembers and the third member, metal gasket to contact the other memberand the third member, and a ller ring to seal with the seal ring and thegasket, and to also contact one of the members and the third member.

11. A sealing assembly for three adjacent members including oisetgrooves in two of the members, a beveled area on each of two of themembers, a filler ring having two beveled faces to cooperate with thebeveled areas in forming two composite grooves, and `a metal seal ringdisposed in each `of said offset grooves and having the opposite sidethereof in one of said composite grooves.

Y 1 HERBERT ALLEN.

